Thread-guard.



A. FROST.

THREAD GUARD.

APPLIOATION FILED OUT. 30, 1912.

1,095,841. Patented May 5, 1914.

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onrrnn srn'rns PATENT onnron .ALONZO FROST, 9F TROY, NEW YORK, ASSIGNOROF ONE-HALF T0 FRANK FROST, OF SCHENECTADY, NEW -YOBK.

THREAD-GUARD.

Specification of Letters Patent.

Patented May 5, 1914.

' Application filed October 30, 1912. Serial No. 728,661.

To all whom it may concern:

Be it known that I, ALoNzo Fnosr, citizen of the United States, residingat Troy, in the county of Rensselaer and State'of New York, haveinvented certain new and useful Improvements in Thread-Guards; and I dohereby declare the following to be a full, clear, and exactdescriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

This invention relates to improvements in take-ups for a sewing machine,and more especially to thread guards for the take-up.

An object of the invention is to provide a cover for the take-up whichwill not only prevent accumulation of dust in the take-up mechanisms,but will also prevent the entanglement of the thread with any part ofthe mechanism when the thread breaks.

A further object of the invention is to provide the cover withadditional means for preventing a wrapping of broken thread around thetake-up cam disks or the shaft driving the samej With these and otherobjects in View the invention comprises certain novel constructions,combinations, and arrangements of parts as will be hereinafter morescribed and claimed.

In the drawings: Figure 1 represents the take-up of the sewing. machinewith my invention applied thereto shown in perspective. Fig. 2 is a topplan view of the cover constituting my invention. Fig. 3 is a verticalsection along the shaft. 7 Heretofore, it' has been found that when thethread broke at the needle or needles of a sewing machine, especiallythat type known as the Union Special, the revolving parts of the'take-upcatch the thread and wrap it around the driving shaft or cam disks,which results in not only waste of the thread, but also in unthreadingthe needles, so that before the operator can resume work it is necessaryto free'the take up of the entangled thread, ret-hread the needles, ripout the unfinished seam, and re sew the entire seam, all of whichis atthe expenseof the operators time and patience. Various attempts havebeen made to prevent this accumulation of thread in the take-up, butnone of them has proved sucally, to comprise a protecting plate, which,acting as a dust guard, also prevents the thread from entering themechanism of the take-up, a tongue extending from the plate into thegroove of the take-up cam disks,-

and an adjustable spring secured to the cover and being in constantengagement with the said cam disks. No additional means is required forholding the plate in 1 The construction thus far described is old in theart, and I do not claim any of it as my invention.

My invention comprises a plate 10 of such outline as to enable the sameto be fitted to the housing 1, said plate being provided with asubstantially rectangular opening 11 which enlarges into an opening 12formed in the plate near the rearof the take-up.

Extending from the enlarged opening 12 is a second substantiallyrectangular opening 13 parallel to opening 11, and having extending intoone end thereof a spring 14. This spring 1 1 may be formed integral withplate 10 or secured to such plate, as may be desired. The openings'lland 13 define a projecting strip 15 which with the plate 10' forms arestricted cut 16in the rear part of opening 13. As shown at 17, theplate 10 is cut so as to fit around the journal of the shaft 2, thisconstruction giving a substantially dust proof fit between the plate andthe rest of the sewing machine. Secured as at 18 is a wire spring 19having a suitable coil formed therein and having 1 formed at the otherend a loop 20 which is adapted to receive a screw 21. The spring 19 isdesigned normally to' press against one of the cam disks, and thepressure between the spring and cam disks may be regulated by the coil.Tapped in one side of the guide supporting block a is a hole 22 adaptedto receive the screw 21, whereby the spring 19 is securely held to thesaid supporting block. 110 V The plate 10 is provided with an indention23, which is in alinement with corresponding recesses in the housing 1,the thread being adapted to pass through said recess and indention. Whenit is desired to adjust the lateral position of the spring 19, it ismerely necessary to turn the cams so that the coil can be bent laterallyaway from the cam disk with the fingers, this lateral bending orstretching of the wire of the spring being accompanied by acorresponding reduction in the size of the coil.

As shown in Fig. 3, the underside of the projection 15 and the undersideof the plate 1 to the right of opening 13 are provided with strips offelt 24 said strips of felt being adapted to extend a short distanceinto opening 13 and engage the outer sides of the cam disks. If desired,these strips of felt may be made of such thickness as will fill thespace between the plate and shaft.

In applying the plate 10 to the take-up device it is merely necessary toraise the guide 5 to an upright position, slip the plate on to thetake-up so that the guide passes through the opening 12, and thecut-away portion 17 is in close contact with the journal box of shaft 2,lower the guide to the position indicated in Fig. 1, and secure loop 20of the spring 19 to the guide block by means of screw 21. From this itwill be seen that the spring 6, acting through the thread guide 5,serves to hold the plate 10 in position, and no other means is employedfor securing the plate.

In the operation of this device, it is to be understood that the shaftis revolving at a high rate of speed, and that the thread is normallyunder tension. If for any reason the thread should break at the needles,and the take-up is not provided with my invention, the loose end of thethread would be thrown upon the shaft 2 by the take-up disk and becomeso entangled with said shaft that in a very short time considerablethread would be wrapped around the shaft.

Experience has shown that in a great number of instances the threadwraps around that part of the shaft between the cam disks and themachine proper, insomuch as the loose end of the thread is nearer thispart of the shaft. By placing my plate upon the take-up, it will be seenthat when the thread breaks, the cam disks throw the same upon thespring 19 which operates to throw the thread to the rear of the.take-up, and thus avoid entanglement with the revolving shaft. However,if only the spring 19 were provided, the free end of the broken threadmight become entangled with the shaft, hence the necessity of providinga plate which will make it impossible for the thread to come in contactwith the revolving shaft. In an endeavor to line the bottom part of theplate lying adjacent the two cam disks with felt, it has been found thatthe felt secured near the rear of the plate is torn off by the camdisks, insomuch as their direction of rotation at that part of the plateis clownward. One of the principal uses of the spring 19 is to supplantthis felt, this spring 19 being formed on one side of the cam disk andextending over that portion of the disk where it has been impracticableto secure felt. As the cam rotates, the flat portions of the cam, suchas are at present in use and a sample of which is illustrated in thedrawings, will carry the thread into the opening in the plate, throughwhich the disk passes, unless the spring 19 is provided. If the springbe not present, the thread will be carried through the opening and willeither wrap around the shaft or be cut by the side of the plate. It isnot necessary that the spring 19 actually engage the disk, but it isdesirable to have the distance between the spring and disk considerablyless than the thickness of the thread which is being used. While aspring has been shown, yet this is not the ony means which may beassociated with the plate for casting off the thread, but is given asone example. The plate 10, together with the felt lined opening 13, andthe projecting tongue lL form an efiective means for keeping the threadfrom the shaft.

In order that operator may be assisted in removing the plate from themachine, an opening is struck from the plate at a point just under oneend of the thread guide, so that the thumb or linger may be slippedeasily under the guide to raise the plate when it is necessary to threadthe take-up mechanism. Of course, it is obvious that the opening couldbe replaced by a recess formed in the plate, in which event the i11-terior of the take-up is kept dust proof.

vVhat I claim is:

1. A thread guard for takeups provided with cam disks comprising a platesurrounding the cam disks, and a spring secured to the plate and adaptedto bear against the cam disks.

2. In a thread guard for take-ups, provided with a plurality of camdisks, a plate surrounding the cam disks, and a tongue extending fromthe plate and between adjacent disks.

3. In a thread guard for take-ups provided with a cam disk, a guardplate having an opening therein, the under part of the plate being linedwith felt around the opening, the cam disk being mounted to rotatethrough the opening and adapted to engage the felt lining.

4. In a thread guard for take ups provided with cam disks, a platehaving an opening therein adapted to receive the cam disks, the edges ofthe opening being lined with felt, a tongue extending from the plate andbetween adjacent cam disks, and a spring secured to the plate andadapted to bear against the side of one of the cam disks.

5. In a thread guard for takeups provided with cam disks, a resilientmember adapted to cast ofi the thread as the disks rotate, one end ofsaid member being fixed with respect to the takeup mechanism, and meansfor supporting the other end of said resilient member.

6. In a thread guard for take-ups provided with cam disks mounted upon ashaft,

a plate surrounding the cam disks and located between the thread and theshaft, and means extending from the plate adapted to cast off the threadas the disks rotate.

In testimony whereof I aifix my signature in presence of two witnesses.

ALONZO FROST.

V Witnesses:

OWEN D. OONNOLLY, C. I. WEBSTER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of ZPatents, Washington, D. G.

